These birds started to colonise Scotland in about 1870 and were fairly common north of
the Lowlands in mainland areas by 1900. They almost all breed inland on rivers and use holes
for their nests. They are hated by many sport fishermen and persecuted (both legally and
illegally) especially in Scotland. Nevertheless they have spread southwards and the first English
breeding was Northumberland (1941) followed by colonisation of the uplands north of a line from
the Flamborough to the Ribble. Now some in the Peak District and even Devon and Wales have
been colonised over the last 30 years. A single pair has been recorded in North-west Ireland, on
and off, for three decades, with breeding proved in Wicklow in 1997.
Further expansion to be confidently expected.